Hours before a young Islip man was bludgeoned, choked and buried alive, one of his co-workers overheard some dark muttering from him, she testified Wednesday in Riverhead.

"I'm going to kill this kid," an agitated Kyle Underhill said as he worked at Manhattan Sweets Boutique Bakery in Islip, co-worker Ashley Genovez testified. "I'm going to jail for murder."

"I asked him if everything was OK," she said, but didn't say if he responded.

StoryTexts before killing show turbulent relationship StoryDNA evidence at murder trial doesn't clear up killingStoryFacebook exchange preceded killing

Within a few hours on Nov. 16, 2011, Underhill, 18, would be dead and buried in a marshy grave in the woods on Brook Street in Islip. Genovez testified at the trial of the man charged with second-degree murder, Thomas Liming, 23, of Islip.

His attorney, Joseph Corozzo of Manhattan, has not contested that Liming killed Underhill, but has suggested he was justified.

Genovez is the third witness to testify Underhill's mood had darkened in the weeks before his death. That period roughly coincided with when Liming, an estranged friend from Islip High School, reconnected with him.

advertisement | advertise on newsday

During questioning by Assistant District Attorney Kathleen Kearon, Genovez said that about an hour after Underhill's muttering about murder, a young man walked into the bakery. He ignored her greeting and walked straight to the kitchen area where Underhill worked, she said.

"He was mysterious, and he had his arm up covering his face," Genovez said. She didn't recognize the man, but the store's surveillance video, played for the jury, showed it was Liming.

She saw Underhill point a finger in Liming's face, but said she couldn't hear what they said.

After that, they spent about 45 minutes cleaning the bakery before it closed, she said. She had never seen a non-employee help Underhill clean, she said.

At one point on the video in response to a question by Kearon, Genovez said Liming was wearing latex gloves as he cleaned, something Underhill never did. Latex gloves with Underhill's blood on them were found near his body.

Earlier Wednesday, Assistant District Attorney Raphael Pearl tried to enter into evidence a Southwest Airlines record indicating Liming's father, Keith Liming, claimed there was a death in the family when he booked a last-minute ticket to return home the night Underhill was killed.

The record was not allowed but testimony on the itinerary will be. Keith Liming and Thomas Liming's twin sister, Elaine, face charges related to what prosecutors say was "evasive" grand jury testimony.